An order to a broker to buy or sell a security at a certain price, with the order expiring at the end of the calendar month if that price does not become available. If the price does become available during that month, the order is executed. A GTM is similar to a day order, but it remains open for the remainder of the month, instead of the remainder of a day. See also: GTC.
A security order that, if it has not been executed, is automatically canceled at the end of the calendar month during which it is entered. Month orders are monitored by the brokerage firms handling the orders rather than by specialists on the floor of an exchange. Also called good-this-month order.